Cranial vena caval syndrome secondary to transvenous pacemaker implantation in two dogs

Superior vena caval syndrome is a rare, but reported complication of transvenous pacemaker implantation in humans. This syndrome can occur secondary to fibrotic and/or thrombotic obstruction of venous blood flow into the right atrium. The therapeutic approach depends on the suspicion of the presence of an active thrombus and may include antithrombotics, angioplasty and/or surgical venoplasty. We describe two dogs that developed severe pleural effusion secondary to stricture formation in the cranial vena cava 4 years after dual chamber transvenous pacemaker implantation. The stenosis was most likely due to fibrosis secondary to the transvenous pacemaker leads. Balloon angioplasty of the lesion resulted in resolution of the pleural effusion in both patients. Balloon angioplasty appears to be a viable therapeutic approach in dogs with cranial vena caval syndrome caused by focal stenotic lesions.     

Echocardiographic evaluation of the effects of medetomidine and xylazine in dogs

The echocardiographic effects of medetomidine and xylazine were evaluated in 6 healthy dogs. Values for echocardiographic variables were significantly different from pre-treatment values after administration of both drugs. The effects of medetomidine were similar to that of xylazine. Because of their cardiac depressant effects, both drugs should be used with care in sick dogs.     

The structure of the upper atmosphere of mars: In situ accelerometer measurements from mars global surveyor

The Mars Global Surveyor (MGS) z-axis accelerometer has obtained over 200 vertical structures of thermospheric density, temperature, and pressure, ranging from 110 to 170 kilometers, compared to only three previous such vertical structures. In November 1997, a regional dust storm in the Southern Hemisphere triggered an unexpectedly large thermospheric response at mid-northern latitudes, increasing the altitude of thermospheric pressure surfaces there by as much as 8 kilometers and indicating a strong global thermospheric response to a regional dust storm. Throughout the MGS mission, thermospheric density bulges have been detected on opposite sides of the planet near 90 degreesE and 90 degreesW, in the vicinity of maximum terrain heights. This wave 2 pattern may be caused by topographically-forced planetary waves propagating up from the lower atmosphere.     

Antioxidant properties of Fusarium head blight-resistant and -susceptible soft red winter wheat grains grown in Virginia

Fusarium head blight (FHB) has emerged as a major threat to wheat crops around the world, and it has been hypothesized that wheat antioxidants may play a role against Fusarium infections. The current study aimed to determine antioxidant properties of FHB-resistant wheat grains as compared to susceptible wheat. The wheat samples were collected from a single growing location (Warsaw, VA) and the same growing season. The results showed that both FHB-resistant and -susceptible wheat grains exerted strong radical scavenging activities against DPPH* radical [0.91-1.53 micromol of Trolox equivalents (TE)/g], peroxyl radical (15.5-24.5 micromol of TE/g), and hydroxyl radical (15.7-35.8 micromol of TE/g). Their total phenolic contents ranged from 888 to 1117 microg of gallic acid equivalents (GAE)/g. Five phenolic acids including ferulic, syringic, vanillic, caffeic, and p-coumaric acids were determined in soluble and insoluble fractions of wheat grains, altogether with a range of 219-389 microg/g. On average, the FHB-resistant wheat group showed significantly higher average values in DPPH* and hydroxyl radicals scavenging activities (30 and 41% higher, respectively) than the FHB-susceptible wheat group.     

Simulated rainfall evaluation of revegetation/mulch erosion control in the Lake Tahoe basin—3: soil treatment effects

Revegetation, or other erosion control treatments of disturbed soil slopes in forested areas and along highways of the Lake Tahoe basin are directed at reduction of sediment loading to waterways reaching the lake. However, following treatment, little vegetation monitoring, or hydrologic evaluation has been conducted either to determine if the various treatments are successful or to assess the duration of erosion control anticipated in the field. Here, we build upon results from use of the portable rainfall simulator (RS) described in the first two papers of this series to evaluate cover and revegetation treatment effects on runoff rates and sediment concentrations and yields from disturbed granitic and volcanic soils in the basin. The effects of slope on rainfall runoff, infiltration and erosion rates were determined at several revegetated road cut and ski run sites. Rainfall simulation (∼60 mm h⁻¹, approximating a 100‐year, 15‐minute storm) had a mean drop size of ∼2·1 mm and approximately 70 per cent of ‘natural’ rainfall kinetic energy. Measurements of: time to runoff; infiltration; runoff amount; sediment yield; and average sediment concentration were obtained. Runoff sediment concentrations and yields from sparsely covered volcanic and bare granitic soils can be correlated to slope. Sediment concentrations and yields from nearly bare volcanic soils exceeded those from granitic soils by an order of magnitude across slopes ranging from 30–70 per cent. Revegetation, or application of pine‐needle mulch covers to both soil types dramatically decreased sediment concentrations and yields. Incorporation of woodchips or soil rehabilitation that includes tillage, use of amendments (biosol, compost) and mulch covers together with plant seeding resulted in little or no runoff or sediment yield from both soils. Repeated measurements of sediment concentrations and yields in the subsequent two years following woodchip or soil rehabilitation treatments continued to result in little or no runoff. Revegetation treatments involving only use of grasses to cover the soils were largely ineffective due to sparse sustainable coverage (< 35 per cent) and inadequate infiltration rates. Copyright © 2005 John Wiley & Sons, Ltd.     

The development of multiple cutaneous inverted papilloma following ovariohysterectomy in a dog

Abstract

CASE HISTORY: Ovariohysterectomy was performed on an adult Cavalier King Charles Spaniel. The skin that had been clipped for surgery was noticed to be erythematous 8 days later.

CLINICAL AND PATHOLOGICAL FINDINGS: Poorly defined patches containing multiple papules were visible bilaterally within the clipped skin. These became larger over the following 2 weeks, and samples were collected for histology. Seven days later, the lesions were multiple raised masses, up to 5 cm in diameter. Histology revealed numerous cup-shaped epidermal proliferations extending into the dermis. The presence of keratinocytes with increased quantities of blue-grey cytoplasm, and koilocytosis suggested papillomavirul infection; Canis familiaris papillomavirus (CfPV-2) DNA was amplified from two separate samples. Complete regression was observed 8 weeks after the lesions had been initially observed.

DIAGNOSIS: Multiple inverted papilloma confined to skin that had been clipped for surgery.

CLINICAL RELEVANCE: This is the first time that the development of canine cutaneous papillomas has been associated with surgery. The nature of the association between surgery and development of the papillomas is uncertain. However, it is possible that damage to superficial skin could promote the formation of papillomas. This is the first identification of CfPV-2 in New Zealand.     

Measuring the spin polarization of a metal with a superconducting point contact

A superconducting point contact is used to determine the spin polarization at the Fermi energy of several metals. Because the process of supercurrent conversion at a superconductor-metal interface (Andreev reflection) is limited by the minority spin population near the Fermi surface, the differential conductance of the point contact can reveal the spin polarization of the metal. This technique has been applied to a variety of metals where the spin polarization ranges from 35 to 90 percent: Ni0.8Fe0.2, Ni, Co, Fe, NiMnSb, La0.7Sr0.3MnO3, and CrO2.